U.S. patent number 6,347,668 [Application Number 09/556,677] was granted by the patent office on 2002-02-19 for relievable check valve assembly for oil wells and water wells.
Invention is credited to John L. McNeill.
United States Patent |
6,347,668 |
McNeill |
February 19, 2002 |
Relievable check valve assembly for oil wells and water wells
Abstract
A relievable check valve assembly having various trigger forms
for oil wells and water wells adapted to control the liquid flow
when inserted tubing is being removed from a well.
Inventors: |
McNeill; John L. (Victoria,
TX) |
Family
ID: |
24222369 |
Appl.
No.: |
09/556,677 |
Filed: |
April 21, 2000 |
Current U.S.
Class: |
166/332.4;
166/105; 166/108; 166/332.7; 166/334.3; 417/444; 417/445;
417/555.2 |
Current CPC
Class: |
E21B
21/10 (20130101) |
Current International
Class: |
E21B
21/00 (20060101); E21B 21/10 (20060101); E21B
034/14 () |
Field of
Search: |
;166/332.4,332.6,332.7,334.3,105,105.3,108,111
;417/552,555.1,555.2,443,444,445 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1388-548 |
|
Apr 1988 |
|
SU |
|
1434-082 |
|
Oct 1988 |
|
SU |
|
Primary Examiner: Bagnell; David
Assistant Examiner: Walker; Zakiya
Attorney, Agent or Firm: Litman; Richard C.
Claims
I claim:
1. A relievable check valve assembly for oil wells and water wells
comprising:
a standing valve unit comprising a circular disc having a centered
throughbore and a plurality of peripheral apertures, a bushing
located within said centered throughbore, and a bell-shaped
standing valve member having a threaded aperture;
a guide pin having a head and a threaded shaft; and
a trigger element having an upturned end with a decreasing width
and a throughbore located at an opposite round end adapted for
passing said guide pin sequentially through said trigger element,
said centered throughbore of the circular disc and the bushing to
attach to the bell-shaped standing valve member;
whereby a conventional travelling valve unit travels down to
contact and depress said guide pin to elevate the bell-shaped
standing valve member for opening up a valve seat to allow any
standing liquid to pass down in a down hole.
2. The relievable check valve assembly according to claim 1,
wherein the trigger element has an inverted U-shaped
cross-sectional configuration with parallel sides extending
downward, and wherein the upturned end is flat.
3. The relievable check valve assembly according to claim 1,
wherein the trigger element has a linear double curved
configuration, wherein the its outer portion is concave upwards and
its inner portion is concave downwards with its apex having a
throughbore.
4. A relievable check valve assembly for oil wells and water wells
comprising:
a standing valve unit comprising a circular disc having a centered
throughbore and a plurality of peripheral apertures, a bushing
located within said centered throughbore, and a bell-shaped
standing valve member having a threaded aperture;
a guide pin having a head and a threaded shaft; and
a trigger element having two Y-shaped elements of equal length with
its legs connected by a hinge, a throughbore adapted for passing
said guide pin sequentially through said trigger element, said
centered throughbore of the circular disc and the bushing to attach
to the bell-shaped standing valve member;
whereby a conventional travelling valve unit travels down to
contact and depress said guide pin to elevate the bell-shaped
standing valve member for opening up a valve seat to allow any
standing liquid to pass down in a down hole.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to valves. More
specifically, the invention is a relievable check valve assembly
for oil or water wells comprising a check valve with a pin, a guide
and triggers of various shapes.
2. Description of the Related Art
The relevant art of interest describes various check valve
assemblies, but none discloses the present invention. There is a
need for an efficient and inexpensive check valve for use in wells
in order to drain fluid out of a plunger type pump and a string of
tubing prior to pulling them out of a well. Removing the fluid,
water or oil, and entrained debris from inside the tubing will
greatly reduce the weight of the string of tubing and thus make the
whole operation easier and safer. The relevant art will be
discussed in the order of perceived relevance to the present
invention.
U.S. Pat. No. 1,543,179 issued on Jun. 23, 1925, to Andrew Miller
et al. describes a valve trip mechanism for bleeding the tubing of
a deep well while the tubing is being extracted. When the working
barrel is pulled toward the surface, an edge of the barrel contacts
the head of a rod which shifts a lever. The lever operates a lift
rod which pushes a ball valve out of its seat within the working
barrel and allow fluid within the tubing to drain back into the
ground and lessen the weight of the tubing being pulled out. The
valve trip mechanism is distinguishable for utilizing a ball valve
motivated by a pivoting lift rod consisting of three segments and a
spring.
U.S. Pat. No. 1,314,070 issued on Aug. 26, 1919, to William H.
McKissick describes a drainage valve for deep well pumps comprising
a first embodiment of FIGS. 1 and 2 drawn to two spaced collars on
bowed springs which cause the opening of a ball valve in a thick
coupling by pushing down a perforated sleeve against the ball and
its compression spring. The second embodiment of FIGS. 3 and 4
entails a standing ball valve resting on an apertured coupling in
contact with a sliding double collared and outwardly bowed springs
element and having an internal T-shaped bolt with extending arms.
The arms immobilize the upper collar member having L-shaped arms by
twisting prior to removal to cause the shaft of the T-shaped bolt
to push up the ball and open the drain pipe. The drainage valves
are distinguishable for requiring ball valves.
U.S. Pat. No. 4,856,756 issued on Aug. 15, 1989, to Linsey L. Combs
describes a well bottom release valve assembly comprising a well
bottom release valve axially aligned just above a down hole pipe. A
short pipe section with a spring biased tight fitting sleeve is
manually controlled from the surface by a cable to open drainage
ports in the sleeve that allow the water contained within to drain
out of the tubing above the down hole pump. The valve assembly is
distinguishable for its above ground manual cable control
element.
U.S. Pat. No. 1,660,486 issued on Feb. 28, 1928, to John A. Friend
describes a drain valve for an inner tube of deep well pumps for
drainage during removal of the inner tube from the well casing. A
casing integrated with the tubing contains an elaborate mechanism
which causes the opening of a drainage hole by movement of a
plunger attached to a lever (and leaf spring) having a projection
which catches in the space between two casings connected by a
coupling. A cam lug of the lever pushes down the plunger against a
ball valve under spring compression away from its seat. The drain
valve mechanism is distinguishable for its numerous parts involving
a lever, a plunger, a ball valve, and a lever.
U.S. Pat. No. 3,995,691 issued on Dec. 7, 1976, to Floyd R.
Hedgecock et al. describes a tool for draining fluids in an oil
well while removing a well conduit. An enclosure of an apertured
tubular housing connected to a well conduit by two couplings
permits drainage from the second bottom coupling when the pushrod
attached to the fluid pump is uplifted. The tool is distinguishable
for its apertured housing and couplings.
U.S. Pat. No. 4,637,471 issued on Jan. 20, 1987, to Paul B.
Soderberg describes a tubing drain valve device useful with heavy
sand-bearing oil and its method of use in a borehole. A first
tubular member of a sub is connected to a pipe string in a casing
with three dogs which engage the casing. A second tubular member
surrounds an upper portion of the first tubular member and is
attached by three shear pins and supported by a compression spring.
As the pipe string is pulled up, the dogs contact the casing wall
and cause the spring to compress for approximately three feet
before the shear pins break and open slots for drainage of the
fluid in the pipe string. The tubing drain valve device is
distinguishable for its required dogs and shear pins.
U.S. Pat. No. 4,645,007 issued on Feb. 24, 1987, to Paul B.
Soderberg describes a sub including a tubing drain valve and its
method of use in a borehole. The sub comprising a tubular member is
inserted in a pipe string by an upper connector and a lower
connector and includes a tubular piston connected to a sucker rod.
The tubular member has a C-spring with six bosses contacting the
tubular member. Three dogs located inside the tubular member are
positioned for contacting two semi-circular members on a lowermost
position of the sucker rod to hold the uplifted pipe string in
place to allow the fluid to drain through aligned ports in the
tubular piston and the tubular member. The sub and tubing drain
valve are distinguishable for requiring a C-spring with bosses,
semi-circular holding members, a hollow piston, and dogs.
U.S. Pat. No. 4,782,895 issued on Nov. 8, 1988, to Jean-Luc Jacob
et al. describes a pumped oil well bottom safety valve
automatically closing when pumping stops and reopening when pumping
resumes. A cylindrical valve body attached at the end of a
production tube and below the valve pump has two cylindrical
vertical channels. The first channel has a valve seat closed by a
flap controlled by a lever and an orifice below the flap. The
second channel is plugged on the bottom and the top with the top
plug abutting a return spring. A push rod attached to the spring
has a transverse second pressure valve and a notch for actuating
the lever and flap. The bottom end of the push rod moves a piston
closing an admission chamber having an orifice. The valve body is
distinguishable for its numerous parts of a two-channelled
body.
U.S. Pat. No. 5,310,005 issued on May 10, 1994, to William W.
Dollison describes a flapper valve assembly with a floating hinge
located between two pipe sections and used in oil and gas wells. A
semicircular flapper body is supported by two pivoting struts and
blocks a flow sleeve or can be folded behind the flow sleeve. The
flapper valve assembly is distinguishable for its flapper and strut
structure.
U.S. Pat. No. 5,425,416 issued on Jun. 20, 1995, to Michael N.
Hammeke et al. describes a formation injection tool for down-bore
in-situ disposal of undesired fluids. The oil and natural gas are
expelled upwards in the upstroke of the pump and the mineral laden
water is disposed underground in the lower disposal formations
during the down stroke. The injection tool consists of three basic
parts comprising an upper intake flow assembly, a middle seal
mechanism and a lower discharge control device. The formation
injection tool is distinguishable for its extensive structure.
Soviet Union Patent Application No. SU 1388-548 A published on Apr.
4, 1988, for Volg Oil Ind. describes an oil well expeller by using
strata energy to drive a pump with its cylinder connected to an
underground separator. The separator has two chambers with a piston
and a poppet valve on a rod in the upper chamber and a compression
spring and stop in a perforated lower chamber. Increasing pressure
in upper chamber by the rising crude causes the piston to rise to
close the poppet valve by the pressure difference. The crude enters
the well tubing and up to decrease the pressure in the separator to
move the piston down to expel the water through the perforations
into the absorbing underground level. The device is distinguishable
for its two fluid separating sections, piston and poppet valve
structure.
Soviet Union Patent Application No. SU 1434-082 A published on Oct.
30, 1988, for Bashkir Oil Ind. describes a production well pump-out
equipment with a drain valve comprising a cylinder having a seat
for a ball and a piston under it with a rod interacting with the
ball when the pump stops operation. The drain valve is
distinguishable for its piston structure.
None of the above inventions and patents, taken either singularly
or in combination, is seen to describe the instant invention as
claimed. Thus, a relievable check valve assembly for oil wells and
water wells solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
A relievable check valve assembly for oil or water wells is shown
comprising a check valve with a pin, a guide and triggers of
various shapes. There is a need for a check valve for controlling
the liquid discharge from wells when removing the tubing.
Accordingly, it is a principal object of the invention to provide a
check valve assembly for oil and water wells.
It is another object of the invention to provide a check valve
assembly for oil and water wells when removing the in-ground
tubing.
It is a further object of the invention to provide a check valve
assembly for oil and water wells when removing the in-ground tubing
for draining the liquid and entrained solids from the tubing back
into the well.
Still another object of the invention is to provide a check valve
assembly for oil and water wells when removing the in-ground tubing
comprising a pin, a guide and a trigger.
It is an object of the invention to provide improved elements and
arrangements thereof for the purposes described which is
inexpensive, dependable and fully effective in accomplishing its
intended purposes.
These and other objects of the present invention will become
readily apparent upon further review of the following specification
and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational cutaway view of a first embodiment for a
relievable check valve assembly for oil or water wells according to
the present invention.
FIG. 2 is a perspective view of the first embodiment showing a
guide inserted in a plate, a pin and a trigger with a conventional
valve.
FIGS. 3A, 3B and 3C are schematic diagrams of the first embodiment
showing the sequence of the valve operation.
FIG. 4 is perspective view of a second embodiment of a valve
assembly having a trigger with an enlarged base.
FIGS. 5A, 5B and 5C are schematic diagrams of a third embodiment
showing the sequence of the valve operation.
FIGS. 6A, 6B, 6C, 6D and 6E are schematic diagrams of a fourth
embodiment showing the sequence of the valve operation.
FIGS. 7A, 7B and 7C are schematic diagrams of a fifth embodiment
showing the sequence of the valve operation.
Similar reference characters denote corresponding features
consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is directed to valves useful in oil or water
wells for draining the fluids when removing well tubing from a down
hole. FIGS. 1, 2, 3A, 3B, and 3C illustrate a first embodiment of a
check valve assembly 10. In FIG. 1, a portion of an upper well
tubing member 12 threadingly joined to a lower valve assembly
casing member 14 are broken away to expose a conventional traveling
valve unit 16 with its valve member 15 and cage 17, and a modified
standing valve unit 18. A push rod 20 shown in an upstroke or open
position is attached to a plunger 22 comprising steel discs 24 with
two enclosed neoprene discs 26. The first embodiment of the check
valve assembly 10 in a closed position comprises a bell-shaped
valve member 28 with an internally threaded stem 30. The valve
member 28 is configured to abut the valve seat 32 formed inside the
valve assembly casing member 14. An apertured planar steel disc 34
with three apertures 36 has a threaded edge 38 which is engaged by
the internal threading 40 at the end of the well tubing 12. A
Teflon bushing 42 is positioned to seat on top of the disc 34 and
its narrow portion to extend slightly below the disc through the
central throughbore 44 in the disc. A flat headed bolt or guide pin
46 with a washer 47 secures a steel trigger 48 configured with a
throughbore 50 and an upturned end 52 to the bushing 42, the disc
34, and the valve member 28.
Turning to the diagrammatic partially sectional views of FIGS. 3A,
3B and 3C, wherein FIG. 3A depicts the stage when the push rod 20
initially begins a downstroke with the traveling valve unit 16 with
its valve member 15 being uplifted from its valve seat 19 by
hydrostatic pressure. The valve member 28 in the standing valve
unit 18 is seated on the valve seat 32 and the trigger 48 has its
upturned end 52 facing up. The fluid trapped in the region between
the two valve units is forced through the open traveling valve unit
16 into the upper region. It should be noted that the relievable
check valve assembly 10 is unaffected by this operation.
FIG. 3B depicts the normal operation of a standard reciprocating
plunger type pump on the downstroke of the traveling valve unit 16.
The upstroke motion causes the upper valve member 15 of the
traveling valve unit 16 to close and the lower valve member 28 to
open temporarily through hydrostatic pressure to force the fluid
below the standing valve unit 18 to be pumped up into the tubing.
Again, the relievable check valve assembly 10 is unaffected by this
operation.
FIG. 3C illustrates the operation of the relievable check valve
assembly 10 when the well operator desires to pull up the string of
tubing or to clear trash out of the standing valve unit 18. The
well operator disconnects the rod string and sets it down on the
bottom of the pump. This action causes the traveling valve member
15 to strike the guide pin 46 to raise the trigger 48 of the
relievable check valve assembly 10 and the standing valve member
28, and simultaneously raise the traveling valve member 15 to cause
the entrained well fluid to drain from the tubing back into the
well.
FIG. 4 illustrates a second embodiment for a modification of a
check valve assembly 54 comprising an inverted U-shaped frame
portion 56 on a body portion 58 having external threading 60 for
securing to an end of the well tubing 12. The frame portion 56 has
a throughbore (hidden) to support a guide pin 62 and a trigger 64
configured with a U-shaped cross-section, an aperture 66, a wide
flanged base portion 68 straddling the frame portion 56, and
tapering to a raised tip 70. The head 46 of the guide pin 62 is
seated with a washer 47 on the trigger 64. The trigger is connected
by the guide pin 62 to the bell-shaped standing valve member 28
seated on a valve seat (hidden) in the lower region of the body
portion 58.
FIGS. 5A, 5B and 5C illustrate a third embodiment 72 utilizing a
double curved trigger 74 standing on a raised Teflon bushing 76 in
the third standing valve unit 78 in a sequence described above for
the second embodiment of FIGS. 3A to 3C.
FIGS. 6A, 6B and 6C illustrate a fourth embodiment 80 utilizing a
hinged trigger 82 in the fourth standing valve unit 84 in a similar
sequence. FIGS. 6D and 6E depict the hinged trigger 82 having two
Y-shaped elements 86 joined by a hinge 88.
FIGS. 7A, 7B and 7C illustrate a fifth embodiment 90 utilizing a
straight, elongated and planar trigger 92 in the fifth standing
valve unit 94.
Thus, various configurations of the trigger 62 have been
illustrated to function effectively in standing valve units of the
present invention.
It is to be understood that the present invention is not limited to
the embodiments described above, but encompasses any and all
embodiments within the scope of the following claims.
* * * * *